CN116217156A

CN116217156A - Recycled mortar and preparation and recycling methods thereof

Info

Publication number: CN116217156A
Application number: CN202211705693.5A
Authority: CN
Inventors: 张晓雪; 陈逸群; 张济涛; 季京安; 宋卉妍; 贡鑫茹; 李博文; 朱敏涛
Original assignee: Shanghai Construction Building Materials Technology Group Co Ltd
Current assignee: Shanghai Construction Building Materials Technology Group Co Ltd
Priority date: 2022-12-29
Filing date: 2022-12-29
Publication date: 2023-06-06

Abstract

The invention provides recycled mortar and a preparation and recycling method of the recycled mortar, wherein the preparation method of the recycled mortar comprises the following steps: step one, determining the proportion of cement, reclaimed sand powder and an exciting agent in reclaimed mortar; step two, dry-mixing cement and reclaimed sand powder in a stirring pot according to the proportion in the step one; step three, sequentially layering and stacking exciting agents in the beaker according to the types; adding water into the beaker while the stirring pot is in a slow stirring state, and stirring by using a glass rod until the exciting agent is completely dissolved; and fifthly, adding water into the stirring pot until the materials are stuck to the inner walls around the stirring pot and do not fall off, pouring into a test mold, standing for molding, demolding and naturally curing. The dissolution time of the sodium sulfate, the sodium silicate, the sodium carbonate and the sodium hydroxide in the beaker from top to bottom is shorter than that of the reverse stacking, the dissolution of the sodium sulfate, the sodium silicate, the sodium carbonate and the sodium hydroxide in the beaker by adding water for multiple times is 2-8 minutes faster than that of the single water adding, the dissolution efficiency is high, and the strength of the prepared regenerated mortar is high.

Description

Recycled mortar and preparation and recycling methods thereof

Technical Field

The invention relates to the technical field of building materials, in particular to recycled mortar and a preparation and recycling method of the recycled mortar.

Background

The production of cement produces carbon dioxide, which can lead to global warming, which can lead to extreme weather frequency, glacier melting, and species extinction. To deal with this situation, carbon transactions are proposed around the world, i.e. others spend money, you reduce emissions, others buy your greenhouse gas reduction at a price of $ 10/ton. Emission reduction measures include the use of less natural raw materials, and the use of industrial and construction waste materials such as recycled concrete sand powder. However, the strength of the reclaimed sand powder is adversely affected by the reclaimed sand powder mixed into cement, mortar or concrete, and the reclaimed sand powder is excited by an exciting agent before the following researches are carried out:

journal (1865 (2015) 12-0031-02) reports the dissolution assisting effect of urea, sodium oxalate, ammonium oxalate and sodium acetate on saturated sodium sulfate solution, and improves the dissolution rate of sodium sulfate. However, it is not reported what means is used to promote dissolution of sodium sulfate, i.e., to increase the dissolution rate.

Zhang Fushun in the paper sodium silicate dissolution and filtration, it is mentioned that vitreous sodium silicate is very insoluble in cold water, and can be dissolved in hot water at normal pressure, but the dissolution speed is slow, and low water consumption is beneficial to the dissolution speed; when solid sodium silicate is dissolved industrially by a steam pressurizing process, the dissolution rate of the sodium silicate solid increases with the pressure. However, it is not reported what means are used to promote dissolution of sodium silicate at normal temperature and pressure.

Patent CN106045361a describes that sodium hydroxide is used as an exciting agent in alkali slag concrete in a solution form, because the sodium hydroxide has high solubility and high dissolution speed, and is convenient to prepare into a solution, but the heat released by the sodium hydroxide rapidly and intensively due to dissolution can accelerate the hydration speed of the alkali slag cement and shorten the insufficient construction time, so that the sodium hydroxide is needed to be dissolved, cooled and then used in industry, and the production link and cost are increased; the sodium hydroxide is not dissolved in advance, and only the retarder is doped into the concrete, but the cost is increased remarkably. The sodium carbonate and the solid sodium hydroxide are used as a composite excitant, and are contacted and dissolved with water at the same time, and form slurry with active powder materials under the stirring action. However, the activator is not dissolved in advance and is easy to disperse, so that dark plaques are formed on the surface of the concrete, and the reinforcing effect is reduced.

The patent CN114620965A prepares alkali-activated cementing materials by taking fly ash slag and steel slag solid wastes as main raw materials, taking plasticizer corrosion inhibitor cement bentonite as a solid additive, waste glass powder and solid alkali metal hydroxide as an exciting agent and sodium lignin sulfonate and polyethylene glycol as rheology modifiers. Wherein, the solid waste/plastic inhibitor cement bentonite solid additive of fly ash slag steel slag=15/85. The invention uses waste glass and alkali metal hydroxide as alkali excitant, and the alkali excitant is mixed with common solid alkali excitant such as: compared with the mixed alkali activator of sodium silicate and sodium hydroxide, the alkali activator of the invention can activate silicate or aluminosilicate in glass powder solid waste by simply adding water because the solid sodium silicate is time-consuming when dissolved, so the alkali activator of the invention is easy to apply and saves time; and the alkali-activated agent does not need thermal excitation, and saves energy. But the mixing amount of the exciting agent/(fly ash slag solid waste + plastic inhibitor cement bentonite solid additive) =67-733%, which is 7 times as much as that of the excited material, and the excitation efficiency is low.

The patent CN108395276A prepares the foam concrete with the volume weight of 500-1100kg/m < 3 >, the strength of 5-15MPa and the heat conductivity coefficient of less than or equal to 0.030W/(m.K) by 65-95% of building waste sand powder, 3-20% of cement and 0.1-5% of foaming agent. But the regenerated sand powder is crushed and ground to the particle size of less than 2mm by waste concrete and bricks, so that the grinding energy consumption is high and the noise is high.

The patent CN112723773A is used for recycling the construction waste. Classifying the construction waste: crushing and preprocessing the building solid waste; sorting; crushing; flushing and screening to obtain regenerated micro powder with the grain diameter of less than 0.15mm, wherein the regenerated aggregate is 4.75-20mm and used for C25-C30 concrete, and the regenerated sand powder is 0.15-4.75 mm and used for mortar; and then carrying out activity excitation on the construction waste: superfine grinding the reclaimed sand powder to generate reclaimed rubber materials, reclaimed cement and reclaimed powder; spraying, dipping and drying the recycled aggregate by using an organosilicon solution and silane; polypropylene fibers are added to the concrete formulation. But the cleaning and grinding procedures are needed, and the energy consumption is high.

The patent CN114573315A adopts 47-85% of ground reclaimed sand powder, cement, lime, gypsum, gas generating component and curing component, and the lightweight concrete with the dry density of 480kg/m3 and the compressive strength of 3.3MPa is prepared through the processes of stirring, pouring, standing, cutting and curing. However, the static stop temperature is 45-55 ℃, the time is 3-5 hours, the curing temperature is 180-230 ℃ and the time is 1-5 hours, and the regenerated sand powder needs to be ground, so that the energy consumption is high.

The patent CN111138135A takes building waste soil as a basic raw material, and a curing agent, regenerated sand powder, plant fiber and water are added to prepare the 3D printing material with the strength of 12.1-15.1 MPa. (construction waste soil + recycled sand powder)/(construction waste soil + recycled sand powder + curing agent) =57 to 63%. The particle size of the regenerated sand particles is 0.21-0.75mm. But the mixing amount of building solid waste (building waste soil and regenerated sand powder) is lower than 80%, the particle diameter of the regenerated sand powder is small, and the crushing energy consumption is high.

The patent CN112592148B is prepared from the raw materials of reclaimed sand powder, higher collar clay, calcium magnesium aluminate silicate, lime Ca (OH) 2, sodium silicate, chemical additives, mineral mixed materials, coarse and fine aggregates and the like by adopting the processes of mixing, vibrating compaction, casting molding, normal-temperature moisture preservation and maintenance for more than 20 days and the like, and the structural material with the compressive strength of 34.6-66.6 MPa is prepared. Wherein the regenerated sand powder/(regenerated sand powder + high collar clay, calcium magnesium silicate and magnesium aluminate) =76-90%, and the excitant lime and sodium water glass accounts for 6.9-21.4% of the mass of the regenerated sand powder. However, the calcium magnesium aluminate silicate is obtained by calcining raw materials mainly containing oxides of silicon, aluminum, calcium and magnesium at 1300-1550 ℃ and then quenching by water quenching, and belongs to magnesite cement (mainly comprising magnesium oxysulfide cement and magnesium oxychloride cement) and special high-strength cement, and the strength can easily reach 62.5MPa; the cost is high; the heat release (1000-1350J/gMgO) is 3-4 times of the hydration heat (300-400J/g cement) of the ordinary Portland cement during hardening, and can not be used together with alkali-exciting agents such as NaOH; when wetted, the surface of the product is easy to generate viscous wet; the strength loss rate of the hardened body after long-term contact with water reaches 60 to 80 percent. The sodium water glass, namely sodium silicate aqueous solution, is prepared by calcining quartz powder and sodium carbonate at 1400 ℃ to generate molten sodium silicate, quenching the molten sodium silicate into particles by water, and dissolving the particles in high-temperature and high-pressure water; is sticky and has large volume, which is unfavorable for practical construction application.

The patent CN103253882A sends the building waste residue into grinding equipment for repeated grinding to prepare the reclaimed sand powder with the size of less than 5 mm. The powder in the building slag regenerated sand powder mixed material is separated, and the building slag regenerated sand powder mixed material is doped in the process of use and is not necessary. "indicates that the reclaimed sand powder can be used as cement-based plate dominant material, mortar and concrete auxiliary material and cement admixture. But no reclaimed sand enhancement is described.

The patent CN110563424A adopts 30-40% of Portland cement, 30-40% of undisturbed ash waste, 10-15% of gypsum, 8-15% of carbide slag waste, 1-3% of glass fiber and 5-15% of excitant to prepare the curing agent, and is applied to soft soil, when the curing agent is applied, each component in the curing agent is added with water and stirred, and then the soft soil is added, and the unconfined compressive strength of the cured soft soil is 2-3 MPa which is 1.5-2.5 times that of the cured soil with pure cement as the curing agent after stirring, compacting, shaping and maintaining. Wherein, the raw ash waste contains more than 50 percent of silicon dioxide and more than 30 percent of aluminum oxide, is similar to fly ash, the carbide slag waste contains 85 percent of calcium hydroxide and 7 to 10 percent of water, which is equivalent to a calcium hydroxide activator, the gypsum contains calcium sulfate dihydrate with the purity of more than 95 percent, which is equivalent to a calcium sulfate activator, the activator contains sodium silicate and calcium chloride, and the curing agent is 20 to 25 percent of the soft soil mass. Cement/(cement+green ash) =43% to 87%. The total mixing amount of the exciting agent carbide slag, the gypsum, the sodium silicate and the calcium chloride accounts for 22% -42% of the curing agent, and the rest components of cement, undisturbed ash and fiber in the curing agent account for 58% -78% of the curing agent. So that the total mixing amount of the exciting agent carbide slag, the gypsum, the sodium silicate and the calcium chloride accounts for 4.4 to 10.5 percent of the soft soil, and the cement, the undisturbed ash and the fiber account for 11.6 to 19.5 percent of the soft soil. Although the cement content is low, the cured soil strength is also low.

The patent CN113233808A sets up the sealed construction area of color steel plate, installs the dust collector, processes old and useless concrete and baked brick alone, pulverizes to below 40mm through the omnipotent breaker for the first time, pulverizes with jaw breaker for the second time, grinds below 0.16mm with the ball mill for 1 hour to obtain the regeneration miropowder, does not need to mix the excitant with it in C20, C30 concrete, economical and practical when being applied to the NaOH mixing amount 3% in C50, the intensity is best when the NaOH mixing amount 5%. The research shows that when the ball milling time is 2 hours, the strength of the regenerated micro powder concrete is reduced, and the regenerated micro powder ball milling time is controlled to be about 1 hour to reach the optimal state. However, the mixing amount of the regenerated micro powder and the proportion of concrete are not described, and the micro powder needs to be ground for 1h, so that the energy consumption is high.

The patent CN112479674A adopts recycled micro powder, mineral powder, fly ash, river sand, broken stone, recycled aggregate, sodium hydroxide solid, water glass, sodium carbonate and water to prepare the recycled concrete, and the compressive strength is 41-47 MPa. And (3) adding no cement into the concrete, standing for 24 hours at the temperature of 205 ℃ after molding, and then carrying out standard curing for 28 days. The particle size of the regenerated micro powder is less than 0.075mm, and the screen residue of 45 micrometers square holes is less than or equal to 45 percent. Firstly, mixing sodium silicate, sodium hydroxide solid and water, standing for 20-48 hours, then putting the regenerated micro powder, mineral powder, fly ash, river sand and regenerated aggregate into a concrete mixer for dry mixing, and finally, respectively adding the sodium silicate-NaOH-aqueous solution and sodium carbonate which are kept standing in advance into the mixer. Regenerated micropowder/(regenerated micropowder+mineral powder+fly ash) =14 to 67 percent, (sodium hydroxide+sodium silicate+sodium carbonate)/(regenerated micropowder+mineral powder+fly ash) =2.4 to 60 percent, and the use amount of the exciting agent is high. The cement firing is changed into the high-temperature curing of the concrete, so that higher requirements are put on a concrete mixing plant, the application is limited, and the popularization value is not realized. And a high energy consumption process is required to obtain the regenerated fine powder with such fineness.

The patent CN111718160A firstly carries out dehydration and drying treatment on sludge/slurry, then prepares regenerated micro powder by utilizing building solid waste, determines the mineral composition proportion and the potential hydration activity of the regenerated micro powder, prepares corresponding alkali-exciting agent and the regenerated micro powder to be uniformly mixed to generate alkali-exciting regenerated micro powder, uniformly mixes the alkali-exciting agent and the regenerated micro powder with proper amount of dehydrated sludge/slurry to solidify the sludge/slurry, and finally carries out CO2 curing treatment on the alkali-exciting regenerated micro powder solidified sludge/slurry. The alkali-activator comprises sodium silicate, sodium hydroxide, calcium hydroxide and active magnesium oxide. The mass ratio of the alkali-exciting agent to the regenerated micro powder is 1-30%. But the strength of the solidified dewatered sludge is only 1.28-2.15 MPa. In addition, in the preparation process of the regenerated micro powder, the regenerated aggregate is required to be soaked in saturated calcium hydroxide solution and then ball-milled until the particle size is less than or equal to 20 microns, and the treatment process is complex and high in energy consumption.

The patent CN111362600B is characterized in that waste cement concrete is crushed and aggregate is separated to obtain waste cement, and the waste cement is ground to the fineness of 500m2/kg to obtain recycled cement; the mass ratio of the regenerated cement to the water is 1:0.35 stirring and mixing uniformly to obtain a flowable regenerated cement mixture, and pouring and molding the regenerated cement mixture to obtain a blank; the embryo is pre-cured for 12 hours in the air atmosphere with the relative humidity of 65 percent and the temperature of 26 ℃, the pre-cured embryo is placed in a pressure tank body, and the embryo is carbonized and cured for 1 hour under the conditions that the purity of CO2 is 99.9 percent and the pressure of CO2 is 0.2MPa, so that the hardened regenerated cement with the compressive strength of 9MPa is obtained. But with a lower strength.

The patent CN114195412B is prepared by uniformly mixing 35-55% of regenerated micro powder, 40-60% of cement clinker powder and 2-5% of gypsum powder, and the regenerated cement is applied to concrete, and the 28-day compressive strength of the regenerated cement is more than 40MPa. The regenerated micro powder does not need to be activated, the mixing amount of the regenerated micro powder is large, and the prepared regenerated cement has excellent performance. The method adopts the technical means that the regenerated sand powder is subjected to multistage grinding and sorting to obtain micro powder with five particle size ranges, and then the regenerated micro powder with different particle size ranges is compounded, so that the micro powder with the particle size ranging from 0 to 5 mu m, 5 mu m to 12 mu m, 8 mu m to 19 mu m, 17 mu m to 34 mu m and 34 mu m to 75 mu m in the regenerated micro powder respectively accounts for 3% -8%, 6% -13%, 13% -25%, 8% -18% and 5% -14% of the regenerated cement. The particle size distribution of the regenerated micro powder is measured by a laser particle size analyzer. When the 28d compressive strength of the regenerated cement is quite high, the total mixing amount of the regenerated micro powder in the 5 particle size intervals is increased by nearly one time from 25% to 48% compared with the regenerated micro powder in the single particle size interval. However, it is industrially difficult to control five fine particle size intervals.

In summary, the construction waste powder recycling industry has the problems that the product strength is low when the reclaimed powder mixing amount is high, the time for dissolving the exciting agent used for activating the reclaimed powder in water is long, the exciting agent is more in components, the mixing amount range is large, the compound proportion is not easy to determine, the product strength of the reclaimed powder is greatly different from 1MPa to 47MPa, the reclaimed raw material recycling treatment process needs to be ground, the product curing process of the reclaimed powder is complex, and the like.

Disclosure of Invention

In view of the shortcomings of the prior art, the invention aims to provide the regenerated mortar and the preparation and recycling method of the regenerated mortar, so that the strength of the regenerated mortar is high when the content of the regenerated powder is high, the time for dissolving the exciting agent used for activating the regenerated powder in water is short, the optimal compounding proportion of the exciting agent can be rapidly determined, the strength of a product prepared by the regenerated powder is stable to about 20.4-24.2 MPa, the regenerated sand powder can be directly utilized without treatment after leaving a factory of building rubbish, and the regenerated mortar can be naturally cured.

To achieve the above-mentioned objects and other related objects,

in a first aspect of the present invention, there is provided a method for preparing recycled mortar, comprising the steps of:

step one, determining the proportion of cement, reclaimed sand powder and an exciting agent in reclaimed mortar;

step two, dry-mixing cement and reclaimed sand powder in a stirring pot according to the proportion in the step one;

step three, stacking the exciting agents in the beaker according to the proportion in the step one in a layered manner in sequence;

adding water into the beaker while stirring with a glass rod at a slow speed, pouring the supernatant into the stirring pot after the first dissolution, grinding the sediment in the beaker, adding water into the beaker again while stirring with the glass rod, pouring the supernatant into the stirring pot after dissolution, and circulating until the excitant is completely dissolved;

And fifthly, adding water into the stirring pot until the materials are stuck to the inner walls around the stirring pot and do not fall off, pouring into a test mold, standing for molding, demolding and naturally curing.

Preferably, the first step specifically includes the following steps:

s1, preliminarily determining regenerated sand powder: the weight percentage range of (reclaimed sand powder and cement) is (A-30)% -A%, and exciting agent: the weight percentage range of the reclaimed sand powder is 0 to (B is 100);

s2, selecting regenerated sand powder: the weight percentages of the (reclaimed sand powder and cement) are A%, (A-10)%, (A-20)%, (A-30)%, the mixing amount of the exciting agent is 0, a test block is prepared, the strength of 7d is measured, and the reclaimed sand powder is determined according to the measurement result: the weight percentage of (reclaimed sand powder and cement) is C, C=A or (A-10) or (A-20) or (A-30);

s3, respectively testing the excitants of sodium sulfate, sodium silicate, sodium carbonate and sodium hydroxide based on C percent to obtain the excitants: preparing test blocks respectively by weight percentage B%, (B10)%, (B100)%, measuring 7D strength, sorting four exciting agents according to excitation strength according to the measurement result, wherein the exciting agent with highest excitation strength is marked as Max, the exciting agent with next highest excitation strength is marked as Maxmi, the exciting agent with next lowest excitation strength is marked as Minmi, the optimal weight percentage of Max and the reclaimed sand powder is D-E%, the optimal weight percentage of Maxmi and the reclaimed sand powder is F-G%, the optimal weight percentage of Minmi and the reclaimed sand powder is H-I%, the optimal weight percentage of Min and the reclaimed sand powder is J-K%, D-E%, F-G%, H-I%, J-K% = [ 0-B% ] or [ B% ] to (B10)% ] or [ (B10)% (B100)%;

S4, taking C% as a basis, preparing test blocks according to the mixing amount of Max being (E/10) of the weight of the reclaimed sand powder, the mixing amount of Maxmi being (E/10) of the weight of the reclaimed sand powder and being 7%, the mixing amount of Maxmi being (G/10) of the weight of the reclaimed sand powder and being 7%, the mixing amount of Minmi being (I/10) of the weight of the reclaimed sand powder and being 4%, the mixing amount of Min being (K/10) of the weight of the reclaimed sand powder and being 7%, respectively preparing test blocks, measuring the strength of 7d, and selecting the optimal mixing amount when Max, maxmi, minmi, min is singly mixed to be L%, M%, N% and P% of the weight of the reclaimed sand powder according to the strength measurement result;

s5, carrying out a re-doping test on Max, maxmi, minmi, min on the basis of C%; the method comprises the following steps:

s5-1, carrying out a re-doping test on Max and Maxmi; according to Max: the weight ratio of Maxmi is 1:1, the total mixing amount is L% of the weight of the reclaimed sand powder; max: the weight ratio of Maxmi is 1:1, the total mixing amount is M% of the weight of the reclaimed sand powder; max: the weight ratio of Maxmi is L: m, the total mixing amount is L% of the weight of the reclaimed sand powder; max: the weight ratio of Maxmi is L/M, and the total doping amount is M% of the weight of the reclaimed sand powder; max: the weight ratio of Maxmi is L: m, the total doping amount is D% of the weight of the reclaimed sand powder; max: the weight ratio of Maxmi is L: m, the total doping amount is E% of the weight of the reclaimed sand powder; max: the weight ratio of Maxmi is L: m, the total mixing amount is F% of the weight of the reclaimed sand powder; max: the weight ratio of Maxmi is L: m, the total mixing amount is G% of the weight of the reclaimed sand powder; preparing a test block, and measuring the 7d strength;

S5-2, carrying out a re-doping test on Max and Minmi; according to Max: the weight ratio of Minmi is 1:1, the total mixing amount is L% of the weight of the reclaimed sand powder; max: the weight ratio of Minmi is 1:1, the total mixing amount is N% of the weight of the reclaimed sand powder; max: the weight ratio of Minmi is L: the total mixing amount is L% of the weight of the reclaimed sand powder; max: the weight ratio of Minmi is L: the total mixing amount of N is N% of the weight of the reclaimed sand powder; preparing a test block, and measuring the 7d strength;

s5-3, performing a compound doping test on Max, maxmi, minmi; according to Max: maxmi: the weight ratio of Minmi is 1:1:1, the total mixing amount is L% of the weight of the reclaimed sand powder; max: maxmi: the weight ratio of Minmi is 1:1:1, the total mixing amount is M% of the weight of the reclaimed sand powder; max: maxmi: the weight ratio of Minmi is 1:1:1, the total mixing amount is N% of the weight of the reclaimed sand powder; max: maxmi: the weight ratio of Minmi is L: m: the total mixing amount is L% of the weight of the reclaimed sand powder; max: maxmi: the weight ratio of Minmi is L: m: the total mixing amount of N is M% of the weight of the reclaimed sand powder; max: maxmi: the weight ratio of Minmi is L: m: the total mixing amount of N is N% of the weight of the reclaimed sand powder; max: maxmi: minmi is L: m: the total doping amount of N is D% of the weight of the reclaimed sand powder; max: maxmi: the weight ratio of Minmi is L: m: the total doping amount of N is E% of the weight of the reclaimed sand powder; max: maxmi: the weight ratio of Minmi is L: m: the total mixing amount of N is F% of the weight of the reclaimed sand powder; max: maxmi: the weight ratio of Minmi is L: m: n, the total doping amount is G%; max: maxmi: the weight ratio of Minmi is L: m: the total mixing amount of N is H% of the weight of the reclaimed sand powder; max: maxmi: the weight ratio of Minmi is L: m: the total doping amount of N is I% of the weight of the reclaimed sand powder; preparing a test block, and measuring the 7d strength;

S5-4, carrying out a re-doping test on Max, maxmi, minmi, min; according to Max: maxmi: minmi: min weight ratio 1:1:1:1, the total mixing amount is L% of the weight of the reclaimed sand powder; max: maxmi: minmi: the weight ratio of Min is 1:1:1:1, the total mixing amount is M% of the weight of the reclaimed sand powder; max: maxmi: minmi: the weight ratio of Min is 1:1:1:1, the total mixing amount is N% of the weight of the reclaimed sand powder; max: maxmi: minmi: the weight ratio of Min is 1:1:1:1, the total mixing amount is P% of the weight of the reclaimed sand powder; max: maxmi: minmi: the weight ratio of Min is L: m: n: p, the total mixing amount is L% of the weight of the reclaimed sand powder; max: maxmi: minmi: the weight ratio of Min is L: m: n: p, the total mixing amount is M% of the weight of the reclaimed sand powder; max: maxmi: minmi: the weight ratio of Min is L: m: n: p, the total doping amount is N% of the weight of the reclaimed sand powder; maxmi: minmi: the weight ratio of Min is L: m: n: p, the total mixing amount is P% of the weight of the reclaimed sand powder; maxmi: minmi: the weight ratio of Min is L: m: n; p, the total doping amount is D% of the weight of the reclaimed sand powder; maxmi: minmi: the weight ratio of Min is L: m: n: p, the total mixing amount is E% of the weight of the reclaimed sand powder; maxmi: minmi: the weight ratio of Min is L: m: n: p, the total mixing amount is F% of the weight of the reclaimed sand powder; maxmi: minmi: the weight ratio of Min is L: m: n: p, the total mixing amount is G% of the weight of the reclaimed sand powder; maxmi: minmi: the weight ratio of Min is L: m: n: p, the total mixing amount is H% of the weight of the reclaimed sand powder; maxmi: minmi: the weight ratio of Min is L: m: n: p, the total doping amount is I% of the weight of the reclaimed sand powder; maxmi: minmi: the weight ratio of Min is L: m: n: p, the total mixing amount is J% of the weight of the reclaimed sand powder; maxmi: minmi: the weight ratio of Min is L: m: n: p, the total mixing amount is K% of the weight of the reclaimed sand powder; preparing a test block, and measuring the 7d strength;

S5-5, selecting a plurality of proportions with optimal performance according to the strength measurement result and the principles of low mixing amount of the exciting agent and high strength of the test block.

Preferably, in the third step, the activator is a composition of sodium sulfate, sodium silicate, sodium carbonate and sodium hydroxide, sodium carbonate, sodium silicate and sodium sulfate are sequentially added into the beaker, and sodium hydroxide, sodium carbonate, sodium silicate and sodium sulfate are sequentially stacked from bottom to top at the bottom of the beaker.

Preferably, in the fifth step, water is added until the material just sticks to the inner wall around the stirring pot and does not fall, the water addition is stopped, stirring is stopped for 5s, stirring is stopped, slurry on the inner wall of the pot and the stirring blade is scraped off, and the pouring can be performed by rapid stirring for 5 s.

The second aspect of the invention provides a recycled mortar, which is prepared by the preparation method of the recycled mortar, and comprises the following components in parts by weight: 100 parts of cement, 400 parts of reclaimed sand powder, 102-112 parts of water and 4-40 parts of exciting agent; the excitant comprises 0-25.45 parts of sodium sulfate, 0-16 parts of sodium silicate, 0-4 parts of sodium carbonate and 0-2.15 parts of sodium hydroxide.

Preferably, the weight percentage of the exciting agent and the reclaimed sand powder is 1-10%, and sodium sulfate in the exciting agent is as follows: sodium silicate: sodium carbonate: sodium hydroxide is 7:4:0:0 or 7:0:1:0 or 7:4:1:0 or 7:4:1:1.

Preferably, the cement is 42.5 grade Portland cement.

Preferably, the recycled sand powder is a mixture of sand and powder with the particle size of 0-0.075 mm, 0.075-0.15 mm, 0.15-0.3 mm, 0.3-0.6 mm, 0.6-1.18 mm, 1.18-2.36 mm, 2.36-4.75 mm and 4.75-9.5mm, wherein the sand powder accounts for 3.1%, 3.5%, 6.8%, 10.7%, 8.1%, 15.5%, 25.6% and 26.7% of the sand powder of the waste concrete which is crushed and screened by a jaw crusher, and the preferable coarse aggregate.

Preferably, the sodium sulfate, sodium silicate and sodium hydroxide are solid particles, the sodium carbonate is solid powder, the sodium hydroxide is superior pure, and the sodium sulfate, sodium silicate and sodium carbonate are analytically pure.

In a third aspect of the present invention, there is provided a recycling method of recycled mortar, comprising the steps of:

t1, crushing the casting-molded and hardened regenerated mortar by using a jaw crusher, and confirming that the whole mortar is crushed to be less than 9.5mm by using a test sieve to obtain regenerated sand powder;

t2, preparing the regenerated mortar by adopting the method of claim 1;

and T3, repeating the steps T1 and T2 until the reclaimed sand powder is recycled for five times when the use of the reclaimed mortar after casting molding is expired or the reclaimed mortar needs to be disassembled and built.

The unhydrated cement particles in the reclaimed sand powder are coated by cement hydrate, contain a large amount of silicon and aluminum components, and are active waste residues after being subjected to high Wen Jileng. The essence of the activity of the waste residue is that the industrial raw material is quenched after being subjected to high temperature, so that the industrial raw material is not converted into stable compounds, and the activity of the compounds is sealed and stored in a glass body state and chemical energy form. Acidic and alkaline substances are used as exciting agents to erode the vitreous body, so that active silicon oxide and aluminum oxide are dissolved out; cement hydration to produce Ca (OH) ₂ Activated silica, activated alumina, ca (OH) ₂ Dissolving in water to produce hydrated calcium silicate gel, which makes the bulk particle become integral material with strength. Sodium silicate and sodium carbonate are strong alkali weak acid salts, and have alkalinity in waterErosion of cement hydrate surrounding the unhydrated cement particles; the sodium hydroxide is alkali, and can erode the active silicon-aluminum component in the reclaimed sand powder; sodium sulfate belongs to strong alkali acid salt, is neutral in water, can react with calcium hydroxide generated by cement hydration to generate sodium hydroxide and calcium sulfate sediment, wherein the alkalinity of sodium hydroxide is stronger than that of the calcium hydroxide generated by cement hydration, and the corrosion effect on reclaimed sand powder is greater than that of cement; meanwhile, sodium silicate reacts with calcium hydroxide to generate sodium hydroxide and calcium silicate, sodium carbonate reacts with calcium hydroxide to generate sodium hydroxide and calcium carbonate, namely sodium sulfate, sodium silicate and sodium carbonate can consume calcium hydroxide generated by cement hydration, so that cement hydration can be accelerated, and the early strength of the regenerated mortar can be improved under the conditions of 20% of cement and 80% of regenerated sand powder. The substances are dissolved in water with the phenomenon of heat absorption and heat release, and the substances which are dissolved and released are relatively large, such as sodium hydroxide and sodium carbonate. Less endothermic material is dissolved, in addition to ammonium nitrate and sodium sulfate. The most endothermic = exothermic substances are dissolved, most of which are water-soluble in life, such as sucrose. The dissolution of sodium silicate is preferably accomplished at a higher concentration, i.e., low water consumption during dissolution; the higher the concentration of NaOH in the solution is, the better the sodium silicate is dissolved, on the one hand, the NaOH can inhibit the sodium silicate hydrolysis process and avoid generating Si0 ₂ Precipitation, on the other hand, of free Si0 ₂ Is easy to carry out, which is advantageous for dissolution.

As described above, the present invention has the following advantageous effects:

(1) In the preparation method of the regenerated mortar, the optimal mixing amount of the exciting agent in single mixing is ingeniously used as the compound mixing proportion, so that the optimal mixing ratio of the exciting agent can be quickly obtained, which is equivalent to the traditional test method, and the test time is shortened from three months to one month.

(2) The fluidity is controlled instead of the water-cement ratio in the preparation method of the regenerated mortar, and the method is based on the visual observation that the slurry is stuck on the inner wall of the stirring pot and does not fall, so that the strength of the regenerated mortar prepared by the method is higher than that of the regenerated mortar prepared by controlling the water-cement ratio, the manpower and the time are saved, and the sewage disposal amount of a concrete stirring station is reduced.

(3) In the recycling method of the recycled mortar, the recycled mortar is completely crushed into the recycled sand powder with the particle size smaller than 9.5mm and is directly applied to the next recycled mortar preparation, and the recycling is performed for five times, so that the repeated screening and the separate utilization of the building waste recycled aggregate and the recycled powder are avoided, and the working efficiency is improved. The regenerated sand powder is recycled for five times without ball milling and calcination, so that the energy consumption and the electric energy consumption of five times of fire coal are saved, the strength of the prepared mortar is about 15.9-24.2MPa, and the mortar has huge economic value.

(4) The dissolution time of the sodium sulfate, the sodium silicate, the sodium carbonate and the sodium hydroxide in the beaker from top to bottom is shorter than that of the reverse stacking, the dissolution by adding water for times is 2-8 minutes faster than that by adding water for a single time, and the dissolution efficiency is high; the dissolution time of the exciting agent is less than or equal to 2min, and the compressive strength of the regenerated mortar is respectively more than or equal to 15.5MPa, 18.3MPa, 20.4MPa, 21.4MPa and 21.9MPa when the doping amount of the exciting agent is 0.1%, 1%, 4%, 7% and 10%.

(5) The heat-absorbing exciting agent does not need thermal excitation, and skillfully utilizes two exciting agents, namely heat absorption and heat release, so that the problem that the heat-absorbing exciting agent needs a heat source to be dissolved and further resources are wasted is avoided, and the problem that the heat release exciting agent is easy to accelerate cement hydration and further shorten construction time is also avoided.

(6) The invention breaks the regenerated mortar into the regenerated sand powder and directly uses the regenerated sand powder in the next circulation, thereby avoiding repeated screening and separate utilization of the construction waste regenerated aggregate and the regenerated powder, and further improving the working efficiency. The regenerated sand powder is recycled for five times without ball milling and calcination, so that the energy consumption and the electric energy consumption of five times of fire coal are saved, the strength of the prepared mortar is about 15.9-24.2MPa, and the mortar has huge economic value.

(7) The invention solves the problems of large reinforcing effect, quick dissolution and low doping amount of the exciting agent.

Drawings

FIG. 1 is a graph showing the time change of the state of the mortar stuck to the inner wall of the stirring pot and the degree of spread of the jump table in comparative example 6.

FIG. 2 is a graph showing the appearance of comparative example 7 recycled mortar and example 2 recycled mortar.

FIG. 3 is a graph of regenerated mortar assessment index and a scatter plot of the activator dosage versus intensity for all formulations of example 1.

Detailed Description

Further advantages and effects of the present invention will become apparent to those skilled in the art from the disclosure of the present invention, which is described by the following specific examples.

The present invention is aimed at researching and developing a regenerated mortar which is quick in proportioning, quick in dissolution promotion, capable of rapidly and largely examining strength data, low in circulating energy consumption, high in strength and stable, and its proportioning method for obtaining, preparing, examining and circulating, and the proportioning method for obtaining regenerated mortar, the preparation method for regenerated mortar, the method for preparing regenerated mortar, the method for examining regenerated mortar, the method for using regenerated mortar, the method for recycling regenerated mortar, the method for 5 and 11 are described by examples 1 and comparative examples 4-3, examples 3 and 8.

In the invention, if no special description exists, the cement is purchased from a Taicang conch cement plant and is P.O42.5 ordinary Portland cement; the reclaimed sand powder is purchased from Shanghai and macro environmental protection technology Co., ltd, and is obtained through a crushing and screening process, and the grain diameter is 0-9.5mm; in the excitant, sodium silicate is purchased from Shanghai trial four Hertz chemical industry Co., ltd, and the molecular formula is Na ₂ SiO ₃ ·9H ₂ O, analytically pure, colorless orthorhombic bipyramid crystals, na ₂ O content 19.3w/% -22.8w/%, na ₂ O and SiO ₂ The ratio of the amount is 1.00-1.06, the chloride (Cl) is less than or equal to 0.01 w/percent, the aluminum (Al) is less than or equal to 0.05 w/percent, the iron (Fe) is less than or equal to 0.05 w/percent, and the heavy metal (calculated by Pb) is less than or equal to 0.001 w/percent; sodium sulfate is purchased from national pharmaceutical group chemical reagent Co., ltd, and has the molecular formula of Na ₂ SO ₄ Analytically pure, wherein the analytically pure is colorless transparent crystalline particles, the content is more than or equal to 99.0 percent, the content of chloride (Cl) is less than or equal to 0.001 w/percent, the content of iron (Fe) is less than or equal to 0.002 w/percent, and the content of heavy metal (calculated by Pb) is less than or equal to 0.005 w/percent; sodium carbonate is purchased from Tianjin chemical company, inc. and has a molecular formula of Na ₂ CO ₃ Analytically pure, white powder, content (Na ₂ CO ₃ ) More than or equal to 99.8 percent, chloridizingThe content of (Cl) is less than or equal to 0.002 w/percent, the content of iron (Fe) is less than or equal to 0.0005 w/percent, and the content of heavy metal (calculated by Pb) is less than or equal to 0.0005 w/percent; sodium hydroxide is purchased from Tianjin Hengxingxiao chemical reagent manufacturing Co., ltd, the molecular formula is NaOH, the superior purity is white crystal particles, the content (NaOH) is more than or equal to 98.0%, the chloride (Cl) is less than or equal to 0.02 w/percent, the aluminum (Al) is less than or equal to 0.001 w/percent, the iron (Fe) is less than or equal to 0.005 w/percent, and the heavy metal (calculated by Pb) is less than or equal to 0.001 w/percent; the water is tap water.

The compressive strength of the regenerated mortar is detected according to GB/T17671-1999 cement mortar strength test method (ISO method); the expansion degree of the recycled mortar is detected according to GB/T2419-2005 cement mortar fluidity determination method.

Example 1

The embodiment provides a proportioning obtaining method of recycled mortar, which comprises the following steps:

s1, determining that the weight percentage of the reclaimed sand powder (reclaimed sand powder plus cement) is 70-100%, and the weight percentage of the exciting agent is 0-10%.

S2, preparing test blocks according to the weight percentages of the reclaimed sand powder (reclaimed sand powder and cement) of 70%, 80%, 90% and 100%, respectively, measuring the 7d strength, and obtaining the best weight percentage of the reclaimed sand powder of 80% according to the strength measurement result.

S3, based on 80% of the weight percentage of the reclaimed sand powder (reclaimed sand powder plus cement), designing 0.1%, 1% and 10% of the weight ratio of sodium sulfate, sodium silicate, sodium carbonate, sodium hydroxide and reclaimed sand powder respectively, preparing test blocks, measuring 7d strength, and sequencing according to the enhancement effect of the exciting agent, wherein the optimal doping amount of the sodium sulfate is 1% -10% of the weight of the reclaimed sand powder, the optimal doping amount of the sodium silicate is 1% -10% of the weight of the reclaimed sand powder, the optimal doping amount of the sodium carbonate is 1% -10% of the weight of the reclaimed sand powder, and the optimal doping amount of the sodium hydroxide is 0.1% -1% of the weight of the reclaimed sand powder: sodium sulfate > sodium silicate > sodium carbonate > sodium hydroxide.

S4, based on 80% of the regenerated sand powder (regenerated sand powder plus cement) in weight percentage, designing that the weight ratio of sodium sulfate, sodium silicate, sodium carbonate and the regenerated sand powder is respectively 4% and 7%, wherein the sodium hydroxide doping amount is not obvious in the range of 0-10% of the weight of the regenerated sand powder, and the test can be omitted. The test block is prepared, the 7d strength is measured, and according to the measurement result, the optimal doping amount of the exciting agent when singly doped is determined to be 7% of the weight of the regenerated sand powder, the doping amount of sodium silicate is 4% of the weight of the regenerated sand powder, the doping amount of sodium carbonate is 1% of the weight of the regenerated sand powder, and the doping amount of sodium hydroxide is 1% of the weight of the regenerated sand powder.

S5, for comparison with a single doping activator, carrying out a re-doping test based on 80% of the reclaimed sand powder (reclaimed sand powder+cement), wherein the specific steps are as follows:

s5-1, designing a sodium sulfate and sodium silicate double doping test; the weight ratio of the sodium sulfate to the sodium silicate is 1:1, a step of; the total mixing amount is 7% of the weight of the reclaimed sand powder; the weight ratio of sodium sulfate to sodium silicate is 1:1, the total mixing amount is 4% of the weight of the reclaimed sand powder; the weight ratio of sodium sulfate to sodium silicate is 7:4, the total mixing amount is 7% of the weight of the reclaimed sand powder; the weight ratio of sodium sulfate to sodium silicate is 7:4, the total mixing amount is 4% of the weight of the reclaimed sand powder; the weight ratio of sodium sulfate to sodium silicate is 7:4, the total mixing amount is 1% of the weight of the reclaimed sand powder; the weight ratio of sodium sulfate to sodium silicate is 7:4, the total mixing amount is 10% of the weight of the reclaimed sand powder; test pieces were prepared and the 7d intensity was measured.

S5-2, designing a sodium sulfate and sodium carbonate double doping test; according to the weight ratio of sodium sulfate to sodium carbonate of 1:1, a step of; the total mixing amount is 7% of the weight of the reclaimed sand powder; the weight ratio of sodium sulfate to sodium carbonate is 1:1, a step of; the total mixing amount is 1% of the weight of the reclaimed sand powder; the weight ratio of sodium sulfate to sodium carbonate is 7:1, a step of; the total mixing amount is 7% of the weight of the reclaimed sand powder; the weight ratio of sodium sulfate to sodium carbonate is 7:1, a step of; the total mixing amount is 1% of the weight of the reclaimed sand powder; test pieces were prepared and the 7d intensity was measured.

S5-3, designing a sodium sulfate, sodium silicate and sodium carbonate triple mixing test; the weight ratio of the sodium sulfate to the sodium silicate to the sodium carbonate is 1:1:1, the total mixing amount is 7% of the weight of the reclaimed sand powder; the weight ratio of the sodium sulfate to the sodium silicate to the sodium carbonate is 1:1:1, the total mixing amount is 4% of the weight of the reclaimed sand powder; the weight ratio of the sodium sulfate to the sodium silicate to the sodium carbonate is 1:1:1, the total mixing amount is 1% of the weight of the reclaimed sand powder; the weight ratio of the sodium sulfate to the sodium silicate to the sodium carbonate is 7:4:1, the total mixing amount is 7% of the weight of the reclaimed sand powder; the weight ratio of the sodium sulfate to the sodium silicate to the sodium carbonate is 7:4:1, the total mixing amount is 4% of the weight of the reclaimed sand powder; the weight ratio of the sodium sulfate to the sodium silicate to the sodium carbonate is 7:4:1, the total mixing amount is 1% of the weight of the reclaimed sand powder; the weight ratio of the sodium sulfate to the sodium silicate to the sodium carbonate is 7:4:1, the total mixing amount is 10% of the weight of the reclaimed sand powder; test pieces were prepared and the 7d intensity was measured.

S5-4, designing four excitant re-doping tests; the weight ratio of the sodium sulfate to the sodium silicate to the sodium carbonate to the sodium hydroxide is 1:1:1:1, the total doping amount is 7%; the weight ratio of the sodium sulfate to the sodium silicate to the sodium carbonate to the sodium hydroxide is 1:1:1:1, the total mixing amount is 4% of the weight of the reclaimed sand powder; the weight ratio of the sodium sulfate to the sodium silicate to the sodium carbonate to the sodium hydroxide is 1:1:1:1, the total mixing amount is 1% of the weight of the reclaimed sand powder; the weight ratio of the sodium sulfate to the sodium silicate to the sodium carbonate to the sodium hydroxide is 7:4:1:1, the total doping amount accounts for 7% of the weight of the reclaimed sand powder; the weight ratio of the sodium sulfate to the sodium silicate to the sodium carbonate to the sodium hydroxide is 7:4:1:1, the total mixing amount is 4% of the weight of the reclaimed sand powder; the weight ratio of the sodium sulfate to the sodium silicate to the sodium carbonate to the sodium hydroxide is 7:4:1:1, the total mixing amount is 1% of the weight of the reclaimed sand powder; the weight ratio of the sodium sulfate to the sodium silicate to the sodium carbonate to the sodium hydroxide is 7:4:1:1, the total mixing amount is 10% of the weight of the reclaimed sand powder; test pieces were prepared and the 7d intensity was measured.

S5-5, according to the principle of low mixing amount and high strength of the exciting agent of the measuring result and the assessment index, selecting 15 formulas with optimal performance, wherein the formulas are respectively as follows: the mixing amount of the sodium sulfate is 7 percent of the weight of the reclaimed sand powder; (2) sodium sulfate and sodium silicate according to a weight ratio of 7:4, compounding, wherein the mixing amount is 7% of the weight of the reclaimed sand powder; (3) sodium sulfate, the mixing amount is 4% of the weight of the regenerated sand powder; (4) sodium sulfate and sodium carbonate according to a weight ratio of 7:1, compounding, wherein the mixing amount is 7% of the weight of the reclaimed sand powder; (5) sodium sulfate and sodium silicate according to a weight ratio of 7:4, compounding, wherein the mixing amount is 10% of the weight of the reclaimed sand powder; (6) sodium sulfate, sodium silicate and sodium carbonate according to the weight ratio of 7:4:1, compounding, wherein the mixing amount is 4% of the weight of the reclaimed sand powder; (7) sodium silicate, the mixing amount is 4% of the weight of the reclaimed sand powder; (8) sodium carbonate, the mixing amount is 1% of the weight of the reclaimed sand powder; (9) Sodium sulfate, sodium silicate, sodium carbonate and sodium hydroxide according to the weight ratio of 7:4:1:1, compounding, wherein the mixing amount is 7% of the weight of the reclaimed sand powder; (10) sodium sulfate and sodium silicate according to a weight ratio of 7:4:1, compounding, wherein the mixing amount is 4% of the weight of the reclaimed sand powder; (11) sodium sulfate and sodium carbonate according to a weight ratio of 7:1, compounding, wherein the mixing amount is 1% of the weight of the reclaimed sand powder; (12) sodium silicate, the mixing amount is 1% of the weight of the reclaimed sand powder; (13) sodium sulfate, the mixing amount is 1% of the weight of the reclaimed sand powder; (14) Sodium sulfate, sodium silicate, sodium carbonate and sodium hydroxide according to the weight ratio of 1:1:1:1, compounding, wherein the mixing amount is 7% of the weight of the reclaimed sand powder; and (15) sodium silicate, wherein the mixing amount is 0.1% of the weight of the reclaimed sand powder.

In the steps, the fluidity is controlled to be constant by adjusting the water consumption when the regenerated mortar is prepared.

The experimental data of the examples are shown in table 1. In table 1, H represents sodium hydroxide, and C represents sodium carbonate; s represents sodium sulfate, and Si represents sodium silicate.

TABLE 1

As is clear from Table 1, the optimum amounts of the respective activators in the single blending were 7% by weight of sodium sulfate, 4% by weight of sodium silicate, 1% by weight of sodium carbonate and 1% by weight of sodium hydroxide (the mass percentages herein refer to the weight percentage of the reclaimed sand powder). The proportion of the exciting agent is consistent during the re-doping, and the intensity of 7 percent of the total doping amount of the exciting agent is higher than the intensity of 4 percent of the total doping amount of the exciting agent and higher than the intensity of 1 percent of the total doping amount of the exciting agent. The method comprises the following steps: s Si C H7/4/1/17% strength 20.6MPa (the weight ratio of sodium sulfate, sodium silicate, sodium carbonate and sodium hydroxide is 7:4:1:1, the total mixing amount is 7% of the weight of the regenerated sand powder), the 7d compressive strength of the prepared test block is 20.6MPa, the following is similar to the above, and S Si C H7/4/1/14% strength 18.8MPa,S Si C H7/4/1/1 1% strength 17.0MPa. S Si C7/4/1 7% strength 21.7MPa, S Si C7/4/1 4% strength 21.7MPa, S Si C7/4/1 1% strength 16.3MPa. S C7/1 7% strength 22.4MPa and S C7/1 1% strength 19.9MPa. S Si 7/4 7% strength 24.2MPa, S Si 7/4 4% strength 20.4MPa, S Si 7/4 1% strength 17.3MPa.

The total mixing amount of the exciting agent is certain in the process of re-mixing, and the exciting agent takes the optimal mixing amount in the process of single mixing as a proportion, so that the strength is higher than that of the exciting agent in equal proportion. The method comprises the following steps: s Si C H7/4/1/1 7% strength 20.6MPa,S Si C H1/1/1/1 7% strength 18.6MPa. S Si C7/4/1 7% strength 21.7MPa, S Si C1/1/1 7% strength 17.3MPa. S C7/1 7% strength 22.4MPa and S C1/1 7% strength 16.8MPa. S Si 7/4 7% strength 24.2MPa, S Si 1/1 7% strength 21.4MPa. This means that when the strength is highest (i.e., when the doping amount is 7%), the strength is larger in the optimum doping amount ratio than in the equal ratio, i.e., the strength is larger in the ratio of S Si C H7/4/1 to 1/1/1/1, the strength is larger in the ratio of S Si C7/4/1 to 1/1, the strength is larger in the ratio of S Si 7/4 to 1/1, and the strength is larger in the ratio of S C/1 to 1/1.

Although the total mixing amount is 7%, the S Si 7/0 is stronger than 7/4, the S Si 7/0 is dissolved in 5 minutes with low efficiency, the S Si 7/4 is dissolved in 2 minutes, and the dissolution promoting effect is realized between the excitants.

Comparative example 1

This comparative example is substantially the same as example 1. The difference is that: 1. the "7d intensity" in all steps was changed to "28d intensity". 2. In the test of S2, the mixing amount of the exciting agent sodium sulfate, sodium silicate, sodium carbonate and sodium hydroxide is respectively 0.04% of the weight of the reclaimed sand powder, 0.07% of the weight of the reclaimed sand powder, 0.4% of the weight of the reclaimed sand powder, 0.7% of the weight of the reclaimed sand powder, 4% of the weight of the reclaimed sand powder and 7% of the weight of the reclaimed sand powder. 3. And deleting the S4.

The test results of comparative example 1 are shown in Table 2.

As can be seen from the combination of tables 1 and 2, the 28-day strength of the test of comparative example 1 is substantially identical to the 7-day strength of the test of example 1, which indicates that the conventional strength test can be adjusted from 28 days to 7 days in the regenerated mortar formulation obtaining method for shortening the test period.

Comparative example 1 the 28 day strength was tested and the single blend formulation was done all at once. Example 1 the 7 day intensity was tested and the single formulation was run in two passes, the first time to determine the optimum amount of each activator in the range of 0-0.1%, or 0.1% -1%, or 1% -10%, and the second time to design the amount of each activator to be 0.04%, 0.07%, or 0.4%, 0.7%, or 4%, 7%, example 1 was run in 18 pot test. Each pot test needs to purchase raw materials, prepare reimbursement vouchers, weigh the materials, make mixtures, adjust water consumption, shaping, test intensity, clean a laboratory, record test data and upload test photos, 18 pot tests are rarely made, the enthusiasm of the research and development of technicians is improved, the performance of products is improved by adjusting the proportion, and compared with the improvement equipment and process, the method has the advantages of low cost, high efficiency and manpower resource saving. Also 13 formulations with maximum activator were obtained, the total time taken for comparative example 1 to make 61 pot mortar was 84 days, the total time taken for example 1 to make 43 pot mortar was 28 days, and the time taken for obtaining the optimum formulation was nearly 2 months earlier.

TABLE 2

Comparative example 2

This comparative example is substantially the same as example 1. The difference is that: compounding the components in the step S5-5, namely S Si 1/1 7%, S Si 1/1 4%, S Si 7/4 7%, S Si 7/4 4%, S Si 7/4 1%, S Si 7/4% and S C1/1 7%, 1 7/1 7%, 1 7/1 7%, S Si C1/1/1 7%, S Si C7/4/1 7%, S Si C7/4/10%, S Si C H1/1/1/1 7%, S Si C H1/1/1/1 7%, S Si C H7/4/1/1/10% "are replaced with" S Si 2/1 7%, S Si 3/1 7%, S SiC 2/2/1 7%, S Si C2/1/1 7%, S Si C H2/2/2/1 7%, S Si C H2/2/1/1 7% ".

The test results of comparative example 2 are shown in Table 3.

TABLE 3 Table 3

Example 1 Complex formulation	Example 1 compressive Strength/MPa	Comparative example 3 Complex formulation	Comparative example 3 compressive strength/MPa
				S Si 7/4 7％	24.2	S Si 2/1 7％	18.2
		S Si 3/1 7％	17.3
				S Si C7/4/1 7％	21.7	S Si C 2/2/1 7％	17.5
		S Si C 2/1/1 7％	15.7
				S Si C H 7/4/1/1 7％	20.6	S Si C H 2/2/2/1 7％	18.3
		S Si CH 2/2/1/1 7％	17.8

As is clear from Table 3, the recycled mortar formulation was designed according to the conventional 1:2:3 ratio, and the strength was lower than that of example 1 and distributed according to the optimum blending amount of 7:4:1:1.

Comparative example 3

This comparative example is substantially the same as example 1, except that: the method changes the flow degree control by adjusting the water consumption in the steps to be constant in the preparation of the regenerated mortar, and controls the water-gel ratio to be constant in the preparation of the regenerated mortar. The "compressive strength and required water-gel ratio of the regenerated mortar described in this comparative example" are shown in Table 4.

As is clear from Table 4, comparative example 3 has a fixed water-gel ratio and a fixed fluidity relative to comparative example 1, and the strength of the regenerated mortar obtained is low. As can be seen from test No. 1 in Table 4, the activator has the effects of reducing the water demand and improving the compressive strength of the regenerated mortar, the cement-cement ratio required by the mortar containing 20% of cement and 80% of regenerated sand powder is 1.20, the compressive strength is 15.0MPa, the cement-cement ratio required by the mortar after the activator is added is reduced to 1.00-1.14, and the compressive strength is increased to 18.3-25.0MPa.

Example 2

The present embodiment provides a preparation method of recycled mortar, in which the proportion of recycled mortar is shown as test number 20 in table 1, and the preparation method includes the following steps:

step one, dry mixing of powder: cement and reclaimed sand powder are dry mixed in a stirred tank.

Step two, stacking exciting agents in a beaker in sequence: sodium hydroxide, sodium carbonate, sodium silicate and sodium sulfate are sequentially added into a beaker, so that the sodium hydroxide, the sodium carbonate, the sodium silicate and the sodium sulfate are stacked from bottom to top at the bottom of the beaker, namely, the stacking priority order is as follows: sodium hydroxide > sodium carbonate > sodium silicate > sodium sulfate.

Step three, the exciting agent is dissolved in a plurality of times: while the mortar stirring pot is kept in a slow stirring state all the time, the exciting agent is stirred by a glass rod while water is added into a beaker, and after the exciting agent is dissolved for the first time, the supernatant is poured into the stirring pot. Grinding the precipitate in beaker with spoon back, and grinding the precipitate with spoon back on paper. Adding water into the beaker again after grinding, stirring for dissolving, pouring the supernatant into a stirring pot, grinding the precipitate, adding water again, and reciprocating until the exciting agent is completely dissolved. Water was added and dissolved 3 times. The last dissolution, rinsing the beaker with water and pouring the rinse water into a stirred tank.

Fourth, adjusting water consumption: adding water until the materials just adhere to the inner walls around the stirring pot and do not fall off, stopping adding water, stirring for 5s, stopping stirring, scraping off the slurry on the inner walls of the stirring pot and the stirring blades, and rapidly stirring for 5s. Pouring into a test mold, forming, demolding and natural curing without vibration compaction.

The preparation method of the regenerated mortar in the embodiment 1 is the same as that of the embodiment, except that if no exciting agent is involved in the second step, no exciting agent is added; in the third step, if the solution can be dissolved into clear solution once without precipitation, the solution does not need to be dissolved for multiple times; if the precipitate is eliminated by dissolving into the supernatant twice, only 2 times of dissolution are required.

In this example, the dissolution phenomenon of the activator is shown in Table 5.

TABLE 5

As can be seen from Table 5, sodium hydroxide and sodium carbonate are dissolved in water to release heat, sodium silicate is dissolved in water to absorb heat without significant change. So that the sodium sulfate becomes hard when meeting water, is not easy to crush by a spoon back and is not easy to melt; sodium silicate hardens in water, but can be crushed and melted well. It can be seen that one of the reasons why the activator is re-mixed and dissolved faster than the single mixed is that the exothermic activator has a dissolution promoting effect on the endothermic activator.

In this example, the dissolution time of the activator is shown in Table 6.

TABLE 6

As is clear from Table 6, the compound activator dissolves faster than the single activator. When the excitant is singly doped, sodium hydroxide and sodium carbonate are instantly dissolved in water, sodium sulfate and sodium silicate are more difficult to dissolve, and particularly, the dissolution of the sodium sulfate is 8 minutes when the concentration of the sodium sulfate is 10 percent, and the dissolution of the sodium silicate is 5 minutes when the concentration of the sodium silicate is 10 percent. The formulation of the compound activator can be dissolved within 2 minutes.

The double doping of sodium sulfate and sodium silicate is faster than the single doping dissolution of both, the dissolution of S7/4 7% takes 2 minutes, the dissolution of S7% takes 5 minutes, and the dissolution of Si7% takes 3 minutes.

Sodium carbonate and sodium hydroxide have dissolution promoting effects on sodium sulfate and sodium silicate, 1 minute is required for S Si C7/4/1 4% dissolution, 3 minutes is required for S4% dissolution, 2 minutes is required for Si 4% dissolution, and C4% instant dissolution is required; s Si C H1/1/1/1 1% dissolution takes 1 minute, S1% dissolution takes 2 minutes, si 1% dissolution takes 1 minute, C1% instant dissolution, H1% instant dissolution. The strength of the compound excitant is lower than that of the single excitant, the S Si 7/4 7% strength is 24.2MPa, the S7% strength is 25MPa, and the Si7% strength is 17.6MPa. S Si C7/4/1 4% strength 21.7MPa, S4% strength 23.4MPa, si 4% strength 21.1MPa, C4% strength 16.5MPa. S Si C H1/1/1/1 1% strength 18.3MPa, S1% strength 19.1MPa, si 1% strength 19.4MPa, C1% strength 20.6MPa, H1% strength 16.3MPa.

The conventional conclusion is that the complex doping intensity of the exciting agent is higher than that of the single doping, the unexpected effect is obtained by the research, the complex doping intensity of the exciting agent is lower than that of the single doping, and the complex doping of the exciting agent is faster than that of the single doping.

Comparative example 4

This comparative example is substantially the same as example 2. The difference is that the stacking order of the exciting agent at the bottom of the beaker is inverted in the second step, and the stacking priority order is changed from 'sodium hydroxide > sodium carbonate > sodium silicate > sodium sulfate' to 'sodium sulfate > sodium silicate > sodium carbonate > sodium hydroxide'. The dissolution time of the inversion of the activator described in this comparative example is shown in Table 7.

TABLE 7

As can be seen from Table 7, the dissolution time of SiCH in the beaker of example 2 was 0-2 minutes in the order from top to bottom, and the dissolution time of SiCH in the beaker of comparative example 4 was 4-8 minutes in the order from bottom to top. This is because the sodium sulfate placed at the bottom of the beaker was first contacted with water when the comparative example 4 was gradually added with water in the beaker, immediately agglomerated, and the sodium sulfate was not melted until the upper sodium hydroxide was contacted with water, and the dissolution-promoting effect was not good, and the sodium sulfate was required to be crushed, added with water, stirred, and dissolved slowly. In example 2, sodium hydroxide placed at the bottommost part of the beaker is firstly contacted with water to dissolve and release heat when water is gradually added into the beaker, and the water is warmed when the uppermost sodium sulfate is contacted with water, so that the sodium sulfate is instantly dissolved into warm water, thereby achieving the effect of twice as much effort.

Comparative example 5

The comparative example is basically the same as example 2, except that the multiple water dissolution of the exciting agent in the third step is changed into one water dissolution, namely "the exciting agent is dissolved once: while the mortar stirring pot is kept in a slow stirring state all the time, adding water into a beaker while stirring an exciting agent by using a glass rod, and pouring an aqueous solution of the exciting agent into the stirring pot after the exciting agent is dissolved. And the amount of water added at one time was equal to the total amount of water added in portions of example 2. The "time for one-time dissolution of the activator described in this comparative example with water" is shown in Table 8.

TABLE 8

As is clear from Table 8, the total amount of water used for dissolution was the same, and the precipitate of the dissolution initiator was 0 to 2 minutes after the dissolution was performed by adding water for several times and stirring. Comparative example 5 it takes 4-10 minutes to add water once and continuously stir until the activator is completely dissolved. It can be seen that example 2 was dissolved in water for 2 to 8 minutes more times than comparative example 5, and the dissolution efficiency was high.

Comparative example 6

The purpose of this comparative example was to verify that the judgment method of stopping the addition of water in step four of example 2 "the addition of water until the material just stuck on the inner wall around the stirring pan did not fall" was able to control the consistency of the slurry fluidity. The concrete method is to test the expansion degree of the mortar jump table by adopting the water-gel ratio of the embodiment 2.

The fluidity of the mortar was verified as described in this comparative example, and is shown in Table 9. The slurry of the comparative example was verified to be stuck to the inner wall of the stirring pan in a state of not falling and to have a degree of spread of table jump, as shown in fig. 1.

TABLE 9

As can be seen from Table 9 and FIG. 1, in example 2, water was gradually added to the reclaimed sand powder and cement, and the fluidity was 175.+ -.5 mm when the slurry was just stuck to the inner wall of the stirring pot and did not fall. It can be seen that the water adding amount is controlled based on the condition that the slurry just sticks to the inner wall of the stirring pot and does not fall off, and is consistent with the water using amount controlled by adjusting the expansion degree of the mortar diving table within the range of 175+/-5 mm. However, comparative example 6 was run for the jump table spread test, 2 minutes for each molding test, 35 seconds for waiting for the jump table to jump 25, 10 seconds for lifting the conical test to scrape the inner wall slurry, 1 minute for testing and recording the mortar spread with a vernier caliper, 3 minutes for pouring out the test specimen and cleaning the wipe, 6 minutes 45 seconds for each sharing, and 290 minutes for 43 (because 43 ratios were designed) sharing. In the embodiment 2, the slurry just sticks to the inner wall of the stirring pot and does not fall off, so that the water adding is stopped, the labor and time are saved, and the sewage disposal amount of the concrete stirring station is reduced under the condition that the same technical effect is ensured (the control expansion degree is within the range of 175+/-5 mm).

Comparative example 7

This comparative example is essentially the same as example 2, except that in step one "powder dry blending: the cement and the reclaimed sand powder are dry mixed in the stirring pot, the cement, the reclaimed sand powder and the exciting agent are dry mixed in the stirring pot, the step two is deleted, and the exciting agent in the step three is dissolved in a separated mode, and the stirring is carried out uniformly by adding water into the stirring pot.

The recycled mortar in which the activator of this comparative example was not dissolved in advance and the recycled mortar in which the activator of example 2 was dissolved in advance are shown in FIG. 2.

As can be seen from FIG. 2, the activator of comparative example 7 was not dissolved in advance, and the activator was locally aggregated in the mortar to appear dark spots. Example 2 the activator was pre-dissolved and dispersed uniformly in the mortar with uniform color.

Example 3

The embodiment provides a regenerated mortar checking method. The assessment indexes of the embodiment are that the doping amount of the exciting agent is 0.1%, 1%, 4%, 7% and 10%, and the qualified compressive strength of the regenerated mortar is 15.5MPa, 18.3MPa, 20.4MPa, 21.4MPa and 21.9MPa respectively. The assessment method in this embodiment is that the dissolution time is less than 2 minutes and the strength is higher than the assessment index, and the assessment method is qualified. The blending amount-strength relationship of the regenerated mortar assessment index described in this example and the exciting agent of all the formulations in example 1 is shown in fig. 3.

In fig. 3, the scattered points are the mixing amount-strength points of the exciting agent in all the formulations in example 1, and the lines are the connecting lines of the qualified compressive strength of the mortar under different mixing amounts of the exciting agent, namely the examination indexes. As can be seen from fig. 3, half of the dispersion points are located above the lines, which indicates that half of the formulations reach the evaluation index, indicating that the evaluation index is suitable.

Comparative example 8

The difference between this comparative example and example 3 is that 43 formulations (see Table 1) of example 1 were intensity ranked using conventional assessment methods.

The 43 formulation intensity ranks in example 1 described in this comparative example are shown in table 10.

Table 10

As is clear from Table 10, when the conventional test method of comparative example 8 was adopted, the strength was 25MPa at the highest when the single blending amount of sodium sulfate was 7% by weight of the reclaimed sand powder, but the dissolution time required for dissolution was 5 minutes, which was not in accordance with the test method of example 3, was less than 2 minutes. The weight ratio of the sodium sulfate to the sodium silicate is 7: and 4, when the total mixing amount is 7% of the weight of the reclaimed sand powder, the strength is higher than 24.2MPa, and only 2 minutes are needed for dissolution, so that the dissolution time required in the assessment method of the embodiment 3 is less than 2 minutes, and the method is an optimal formula. When the blending amount of sodium sulfate is 10% of the weight of the reclaimed sand powder, the strength is 21.7MPa, the formula with the strength rank of 7 being high in 43 formulas is judged according to the strength rank list of comparative example 8, and the formula is not qualified according to the assessment index of '10% strength of the exciting agent >21.9 MPa' of example 3. Although the evaluation index of example 3 was not used, the same strength as 21.7MPa was judged based on the low blending amount and high strength, and the S Si C7/4/1 7% formulation was more excellent than the S10% formulation by saving the activator. However, the assessment index of example 3 is more quantitative and objective, and facilitates rapid mass analysis of data, and the scattered point is qualified above the line. The strength of the formula 1 is low, the mixing amount of the exciting agent is low, the strength of the formula 2 is high, and the mixing amount of the exciting agent is high, so that the two cases cannot be simply compared and the advantages and disadvantages of the two cases are analyzed. However, by comparing the values of the examination indexes in the embodiment 3, the advantages and disadvantages of the comprehensive performances of the two can be rapidly compared. For example, the test number 21 formula S Si 1/1 4% of example 1 has a strength of 19.4MPa, the test number 20 formula S Si 1/1 7% has a strength of 21.4MPa, and it can be rapidly judged that the formula S Si 1/1 4% has poor comprehensive performance below the line in FIG. 2, and the formula S Si 1/1 7% is better above the line in FIG. 2.

Example 4

The embodiment provides a recycling method of regenerated mortar. The composition of the recycled mortar material in this example was the same as that of test number 22 in example 1. The strength of the mortar prepared by recycling reclaimed sand powder in the embodiment is shown in Table 11. The recycling method of the regenerated mortar in the embodiment comprises the following steps:

and T1, crushing the regenerated mortar by using a jaw crusher, and confirming that the whole mortar is crushed to be less than 9.5mm by using a test sieve to obtain regenerated sand powder for secondary recycling.

T2, preparing the regenerated mortar by adopting 20% of cement, 80% of regenerated sand powder, 1.04% of water-cement ratio and 7/4 7% of excitant S Si.

And T3, repeating the steps T1 and T2 until the reclaimed sand powder is recycled for five times when the service life is expired or the reclaimed sand powder needs to be disassembled and built.

TABLE 11

As is clear from Table 4, the strength of the reclaimed mortar prepared from the reclaimed sand powder for the first time was 24.2MPa, and the reclaimed mortar was crushed to reclaimed sand powder and applied again to this formulation to prepare mortar, the strength of which was 23.5MPa. And the third, fourth and fifth times of cyclic application of the regenerated sand powder to prepare the regenerated mortar, wherein the strength of the regenerated mortar is 22.2MPa, 19.9MPa and 15.9MPa respectively. The recycled mortar is completely crushed into the recycled sand powder and is directly used in the next circulation, so that the repeated screening and the separate utilization of the recycled aggregate and the recycled powder of the construction waste are avoided, and the working efficiency is improved.

Comparative example 9

The difference between this comparative example and example 4 is that in step T1, the recycled mortar is crushed by a jaw crusher, ground by a ball mill to 0.075mm or less, and finally calcined in a 1000 ℃ furnace for 3 hours to obtain recycled fine powder. And the regenerated sand powder in T2 and T3 is changed into regenerated micro powder. The strength of the slurry produced by the recycled calcined regenerated micropowder described in this comparative example is shown in Table 12.

Table 12

As is clear from table 12, the regenerated mortar was crushed, ball-milled, and calcined to form a regenerated fine powder, which was then directly used in the next cycle. Although the strength of the recycled regenerated clean slurry is kept unchanged, the energy consumption in the processes of high-temperature calcination, ball milling and the like is too high, the aggregate is absent in the micro powder, and the strength of the regenerated clean slurry is lower and is about 13.8-15.1 MPa. Whereas example 4 does not require ball milling or calcination, the strength is about 15.9-24.2 MPa. The cement yield is reported to be 12.31 million tons consuming 1.31 million tons of standard coal. The embodiment 4 circularly uses the reclaimed sand powder for five times without calcining, saves the energy consumption of the fire coal for five times, and has huge economic value.

Comparative example 10

The difference between this comparative example and example 4 is: and in the step T1, the regenerated mortar is crushed by a jaw crusher and is ground to be less than 0.075mm by a ball mill, so that the recycled regenerated micro powder is obtained. And the regenerated sand powder in T2 and T3 is changed into regenerated micro powder.

The strength of the slurry prepared by recycling the ball-milled regenerated micro powder is shown in Table 13.

TABLE 13

As is clear from table 13, the regenerated mortar was crushed and ball-milled into regenerated fine powder, and the powder was directly used in the next cycle. The regenerated micro powder needs ball milling every time for repeated use, the energy consumption is high, and the strength of the regenerated clean slurry is low due to the fact that the micro powder is not calcined and the aggregate is absent.

The electric energy consumption is always a headache problem of a construction waste treatment plant, in the construction waste treatment process, the electric power consumption of the ball mill is maximum, the power of a common motor is hundreds of kilowatts, and the energy consumption of large-sized ball mill equipment is higher. Therefore, in the industrial production process, how to improve the strength of the regenerated building material product is important under the condition of not reducing the energy consumption. In the embodiment 4, the reclaimed sand powder is recycled for five times without grinding, so that the energy consumption of ball milling is saved for five times.

Example 5

The present embodiment provides a recycled mortar. The raw material composition and performance of the recycled mortar described in this example are shown in table 14; the preparation method of the regenerated mortar is shown in example 2.

TABLE 14

As is clear from Table 14, the compressive strength of examples 5-1 to 5-8 was 20.4 to 24.2MPa, and the dissolution time of the activator was 0 to 2 minutes. Comparative example of example 5: the formulation in Table 1 of example 1 was the comparative example of example 5, except that test numbers 6, 17, 22, 23, 24, 28, 34 and 40 were used. As is clear from Table 1, test No. 1 is a blank group in which no activator was added, cement 20%, reclaimed sand powder 80%, water-gel ratio 1.20, and compressive strength 15.0MPa.

The compressive strength of examples 5-1 to 5-8 was 36% -61% higher than that of the blank. The test number 4 shows that the regenerated mortar has 10% of sodium hydroxide and 11.4MPa of compressive strength, which is lower than that of the blank control group, and the unsuitable consumption of the exciting agent can reduce the strength of the regenerated mortar.

The compressive strength of test numbers 2, 3, 7, 10, 15, 26, 32 and 35 is about 15-16MPa, and the strength is not improved compared with that of a blank control group. Therefore, the strength of the regenerated sand powder-based mortar with high mixing amount is difficult to be improved by adopting an exciting agent scheme, and the mortar can be successfully prepared without conventional test of a plurality of proportions.

The compressive strength of test numbers 18, 19, 25, 27, 31, 37, 39 and 41 is about 17-18MPa, and the strength is not obviously improved compared with that of a blank control group.

The compressive strength of test serial numbers 8, 9, 14, 36 and 43 is about 19-22MPa, and the strength of the test serial numbers is obviously improved compared with that of a blank control group, but the strength of unit doping amount is lower than that of the test serial numbers, 9, 14, 36 and 43, and is lower than the requirement of an examination index proposed in the patent: the mixing amount of the exciting agent is 7 percent, the strength is more than or equal to 21.4MPa, and the mixing amount of the exciting agent is 10 percent, the strength is more than or equal to 21.9MPa.

The amounts of the activators used in test Nos. 11, 16, 21, 29 and 38 were 1% to 4%, and the compressive strength was about 19MPa, but the amounts of the activators used were low, but the compressive strength was not excellent enough.

Test serial numbers 20, 33 compressive strength is higher than 20MPa, also is higher than the examination index requirement that this patent put forward: the strength of the activator with the doping amount of 7% is more than or equal to 21.4MPa, but the strength is lower than that of the examples 5-1 to 5-8 with the same doping amount.

The compressive strength of test serial numbers 12 and 13 is higher than 23MPa, but the dissolution time of the exciting agent is 3-5 min, which does not meet the requirement of the examination index proposed by the patent: the dissolution time is less than or equal to 2min.

Therefore, when the mixing amount of the reclaimed sand powder is up to 80%, the exciting agent has a large reinforcing effect, but is slowly dissolved, so that the strength of mortar is greatly improved by adopting the exciting agent with a low mixing amount, meanwhile, the quick dissolution of the exciting agent is ensured, and the exciting agent needs to be overcome: the problems of large enhancement effect, quick dissolution and low mixing amount are mutually restricted.

Comparative example 11

The difference between this comparative example and examples 5-5 is: the comparative example was free of the addition of an activator, cement/(cement+reclaimed sand powder) =60%, reclaimed sand powder/(cement+reclaimed sand powder) =40%. The raw material composition and properties of the recycled mortar of this comparative example are shown in Table 15.

TABLE 15

As is clear from Table 15, the strength also reaches 21MPa, and comparative example 11 does not use an exciting agent, and the reclaimed sand powder can only be doped into 40%; examples 5-5 by using the activator formulation of the present patent, the blending amount of the reclaimed sand powder can be increased to 80%, and the blending amount of the reclaimed sand powder is doubled.

In a word, the invention provides the regenerated mortar which has the advantages of dissolution promotion, recycling, quick proportioning, simple and convenient control of fluidity, quick and massive analysis of the advantages and disadvantages of the formula, and the proportioning obtaining, preparing, checking and recycling method thereof, and based on the characteristics of simplicity and high efficiency, the invention can promote the generation of a large number of formulas of solid waste based inorganic products with high doping amount, and the formula optimization is the most labor and cost saving compared with the improvement of equipment and technology. In the formula optimization, the proportioning design, the quick preparation, the performance test and the index measurement require a great deal of time to do a great deal of mental and physical labor, so that scientific researchers often focus on the forehead.

The above embodiments are merely illustrative of the principles of the present invention and its effectiveness, and are not intended to limit the invention. Modifications and variations may be made to the above-described embodiments by those skilled in the art without departing from the spirit and scope of the invention. Accordingly, it is intended that all equivalent modifications and variations of the invention be covered by the claims, which are within the ordinary skill of the art, be within the spirit and scope of the present disclosure.

Claims

1. The preparation method of the regenerated mortar is characterized by comprising the following steps of:

2. The method for preparing recycled mortar according to claim 1, wherein the first step specifically comprises the following steps:

3. The method for preparing recycled mortar according to claim 2, wherein in the third step, the activator is a combination of sodium sulfate, sodium silicate, sodium carbonate and sodium hydroxide, sodium carbonate, sodium silicate and sodium sulfate are added into the beaker in sequence, and sodium hydroxide, sodium carbonate, sodium silicate and sodium sulfate are stacked in sequence from bottom to top at the bottom of the beaker.

4. The method for preparing regenerated mortar according to claim 1, wherein in the fifth step, water is added until the material just sticks to the inner wall around the stirring pot and does not fall, water addition is stopped, stirring is stopped for 5s, stirring is stopped, slurry on the inner wall of the pot and the stirring blade is scraped off, and pouring can be performed by rapid stirring for 5 s.

5. The recycled mortar is characterized by being prepared by the preparation method of the recycled mortar according to any one of claims 1-4, and comprises the following components in parts by weight: 100 parts of cement, 400 parts of reclaimed sand powder, 102-112 parts of water and 4-40 parts of exciting agent; the excitant comprises 0-25.45 parts of sodium sulfate, 0-16 parts of sodium silicate, 0-4 parts of sodium carbonate and 0-2.15 parts of sodium hydroxide.

6. The recycled mortar of claim 5, wherein the weight percentage of the activator and the recycled sand powder is 1-10%, and sodium sulfate is contained in the activator: sodium silicate: sodium carbonate: sodium hydroxide is 7:4:0:0 or 7:0:1:0 or 7:4:1:0 or 7:4:1:1.

7. a recycled mortar according to claim 5, wherein said cement is 42.5 grade portland cement.

8. A recycled mortar according to claim 5, wherein the recycled sand powder is a mixture of sand and powder of 0-9.5mm remaining after the waste concrete is crushed and sieved by a jaw crusher, preferably coarse aggregate, wherein the sand powder ratio of 0-0.075 mm, 0.075-0.15 mm, 0.15-0.3 mm, 0.3-0.6 mm, 0.6-1.18 mm, 1.18-2.36 mm, 2.36-4.75 mm, 4.75-9.5mm is 3.1%, 3.5%, 6.8%, 10.7%, 8.1%, 15.5%, 25.6%, 26.7%, respectively.

9. A recycled mortar according to claim 5, wherein sodium sulfate, sodium silicate and sodium hydroxide are solid particles, sodium carbonate is solid powder, sodium hydroxide is superior purity, sodium sulfate, sodium silicate and sodium carbonate are analytically pure.

10. The recycling method of the regenerated mortar is characterized by comprising the following steps of:

t2, preparing the regenerated mortar by adopting the method of claim 1;